The problem is that deforestation pays. That's the reality that defines a challenge that affects everything from our climate and the cost of our food, to the fate of wildlife and global efforts to eradicate poverty.

Most deforestation occurs because people around the world want wood, food, biofuels and other products that companies can provide from forest-converted land. As a result, any measures to limit deforestation that do not address this demand will struggle to make an impact. And while there have been some efforts to influence demand in ways that limit deforestation – these efforts have been unco-ordinated or have targeted different drivers of deforestation in a patchy way.

Demand-side measures that aim to limit deforestation range from legislation and public sector initiatives to industry-led standards, voluntary certification schemes and consumer-focused campaigns – such as when Greenpeace targeted toymaker Mattel over its use of cardboard made by a company known to destroy Indonesian rainforests.

These measures cover not only timber but also other products from formerly forested land, such as soy and palm oil, beef and biofuels. But a ban – such as the new EU regulations that ban sales of illegally harvested timber products – or a certification scheme that only covers one commodity could lead to what we call "leakage". This means progress in some areas could be more than offset by slippage elsewhere. While forest may be saved in one area, it may be lost in another. And even certified "deforestation-free" products occupy only a small share of the market, because consumers tend to be unwilling to pay a premium.

The International Institute for Environment and Development, forest footprint disclosure project, and the Prince's Rainforests Project wanted to assess whether it is possible to enhance demand-side interventions to reduce deforestation – and, if so, how. We wanted to identify what works best and whether measures associated with one commodity can be applied to others. And we wanted to understand, too, how the aspirations of people in consumer and producer countries factor into the design of such measures.

Last month we convened a meeting of forestry and trade specialists at the Royal Society to identify answers to these questions. Participants included policymakers, product certifiers, NGO staff, financiers and business people, representing a range of commodities and roles in the supply chain.

Speakers noted how the business case for avoiding deforestation remains unmade. Indeed, it is hard to find two people who agree on what sustainability even means. Part of the problem is that it depends on who is "selling" the idea of sustainability – and to whom. Nor is it clear that certification has any impact on deforestation overall, especially when eco-labels proliferate and governments are happy to support the schemes that exist rather than pushing them to improve.

What's clear is that we need a variety of measures that work in concert – legislation that enforces what campaigns call for, certification that has a genuine impact on deforestation rates, and input from the finance sector to address gaps that prevent producers from meeting demand-driven standards or traceability.

We also need ways to bring in the free-riders and non-conformers, whether companies or countries. And we need public sector interventions to focus less exclusively on the timber sector and address other major drivers of deforestation – such as agriculture.

Companies, governments, consumers and campaigners can all influence the supply chains that reach around the world to threaten forest landscapes. The good news is that there is growing awareness of the need for demand-side measures to deliver wider sustainability goals of environmental and social responsibility while securing economic incentives such as competitiveness and resilience. The bad news is that, as the horsemeat scandal affecting meat productions in the UK right now shows, it is all too easy for big brands to know little about their supply chains.

The G8 leaders who meet in the UK in June have a role to play. They can enact steps that can bring standards for consumer markets into convergence. They can act to ensure government subsidies reduce deforestation instead of stimulating it. Given the importance of cost savings to stimulating increased demand for deforestation-free commodities, they can initiate a review of available options under the different demand-side initiatives at all stages of the supply chain, while not compromising social and environmental integrity. And they can agree ways to make natural capital accounting a basic element of the businesses of the future.

Simon Milledge is a principal researcher in the forest team at the International Institute for Environment and Development